Iron in cytosolic ferritin can be recycled through lysosomal degradation in human fibroblasts

Derek C Radisky, Jerry Kaplan

Research output: Contribution to journalArticle

107 Citations (Scopus)

Abstract

Examination of the mechanism of intracellular iron recovery from lysosomally-degraded ferritin in vivo has been complicated by the continuous flux of cellular iron through ferritin molecules. Here we incubated human fibroblasts with cationic ferritin, a derivative of horse spleen ferritin, as a technique for delivering immunologically distinct ferritin molecules directly to lysosomes. Using this method, we found increased endogenous ferritin levels after the cellular degradation of cationic ferritin, demonstrating that cells can utilize lysosomal ferritin to produce increased cytosolic ferritin levels. Further, using an in vitro assay, we showed that isolated lysosomes degrade endogenous ferritin in a time- and temperature-dependent manner. These results are consistent with a model in which cytosolic ferritin is taken into the lysosomes and degraded. The solubilized iron from the ferric core could then be transported across the lysosomal membrane back into the cytosol.

Original languageEnglish (US)
Pages (from-to)201-205
Number of pages5
JournalBiochemical Journal
Volume336
Issue number1
StatePublished - Nov 15 1998
Externally publishedYes

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Fibroblasts
Ferritins
Iron
Degradation
Lysosomes
Molecules
Cytosol
Horses
Assays
Spleen
Fluxes
Derivatives
Membranes
Recovery
Temperature

ASJC Scopus subject areas

  • Biochemistry

Cite this

Iron in cytosolic ferritin can be recycled through lysosomal degradation in human fibroblasts. / Radisky, Derek C; Kaplan, Jerry.

In: Biochemical Journal, Vol. 336, No. 1, 15.11.1998, p. 201-205.

Research output: Contribution to journalArticle

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